Project Summary Hysterectomy is the second most commonly performed surgical procedure among United States (US) women ages 18-64 (after cesarean section)1 and there is concern regarding differential rates across racial/ethnic groups2. Black/White racial differences in treatment by hysterectomy have been well documented3?6, as the majority of research focuses on this particular comparison. However, this focus has left the study of disparities in hysterectomy among women of other racial/ethnic groups vastly under-represented in published literature. Persistent differential hysterectomy rates by race/ethnicity is troubling and cause for further examination. The unique and powerful core data source for this study - medical claims-based surveillance data from 2011- 2014 (N=44,658) in the State of North Carolina (NC) - allows for insight into populations for which published literature on treatment with hysterectomy is practically non-existent. This project uses data from NC to address three research aims: 1) Describe racial/ethnic variation in hysterectomy rates in North Carolina between 2011 and 2014, both for the state as a whole and for smaller areas (i.e., counties or groups of counties); 2) Identify the social and economic contexts associated with higher/lower county-level rates of hysterectomy, how these contexts differ by racial/ethnic group, and in turn how these contexts help explain racial/ethnic disparities in rates of hysterectomy; and, 3) Identify the healthcare contexts associated with higher/lower facility-level rates of hysterectomy, how these healthcare contexts differ by racial/ethnic group, and in turn how these contexts help explain racial/ethnic disparities in rates of hysterectomy. For each aim, specific attention will be given to characterizing hysterectomy rates, patterns, and covariates among those demographic groups that are least represented in the literature, including American Indians, Hispanics, and Asians. Before we are able to consider what an ideal rate of hysterectomy would be, we first need to better understand disparities in rates across groups and how social, economic, and healthcare contexts produce different rates in different areas. Analytic methods will include multilevel regression using fixed and random effects. By linking surveillance data to rich contextual databases, this work will examine the non-clinical and contextual factors associated with hysterectomy rates in NC and build greater understanding of factors that impact disparities in this common and invasive procedure. Results from this research may be used to inform future health and social policy geared toward the reduction of hysterectomy rates among racial/ethnic minority groups. The proposed training plan focuses on unique and complementary foci in epidemiology, demography, and health services, the combination of which moves well beyond the applicant's graduate program requirements. To support this work, the applicant has assembled a strong mentorship team, lending expertise in methods for studying racial/ethnic health disparities, familiarity in working with administrative data sets, and knowledge of clinical decision making. This training would not be possible without NRSA support.